YOKOGAWA DPharp EJXC40A, Руководство пользователя

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<8. Maintenance>
8-7
IM 01C25W05-01EN
8.5 Troubleshooting
If any abnormality appears in the measured values,
use the troubleshooting flow chart below to isolate
and remedy the problem. Since some problems
have complex causes, these flow charts may
not identify all. If you have difficulty isolating or
correcting a problem, contact Yokogawa service
personnel.
8.5.1 Basic Troubleshooting
First determine whether the process variable
is actually abnormal or a problem exists in the
measurement system. If the problem is in the
measurement system, isolate the problem and
decide what corrective action to take.
This transmitter is equipped with a self-diagnostic
function which will be useful in troubleshooting.
Refer to subsection 8.5.3 for details.
Abnormalities appear in measurement.
: Areas where self-diagnostic offers support
Is process variable
itself abnormal?
Inspect the
process system.
Isolate problem in
measurement system.
Does problem exist in
receiving instrument?
Check/correct
environmental conditions.
Inspect receiver.
Check transmitter.
Check/correct operating
conditions.
Measurement system problem
F0805.ai
YES
NO
NO
YES
Environmental conditions
Operating conditions
Transmitter
8.5.2 Troubleshooting Flowcharts
YES
NO
NO
YES
NO
NO
YES
YES
NO
YES
Connect HART configuration tool and check self-diagnostics.
Does
the self-diagnostic
indicate problem
location?
Is the polarity of the
externally wired power
supply correct?
Is the DRS cable
connected properly?
Are power supply
voltage and load resistance
correct?
Is there
continuity through the
transmitter loop wiring?
Do the loop numbers
match?
Contact Yokogawa service personnel.
Find/correct broken conductor or
wiring error.
Refer to section 5.3 to check/correct
polarity at each terminal from power
supply to the terminal box.
Refer to section 4.3 to check/correct
the DRS cable connection.
Refer to section 5.6 for rated voltage
and load resistance.
Refer to error message summary in
Subsection 8.5.3 to take actions.
F0806.ai
The following sorts of symptoms indicate that transmitter
may not be operating properly.
Example : • There is no output signal.
• Output signal does not change even though
process variable is known to be varying.
• Output value is inconsistent with value
inferred for process variable.